Modeling and Experiments of Electron Beam Transport in Large-Area Diodes for KrF Laser Driven ICF
Abstract
The goal of this research is to understand electron-beam generation, transport, and energy deposition in an electron beam driven KrF laser in order to reduce extraneous loss mechanism and improve efficiency. To date we have identified a ``transit time instability'' in the diode that can produce a large spread in electron energies incident on the Foil/Hibachi structure. Measurements and simulations indicate that the energy spread introduced by the instability in the diode leads to enhanced deposition in the Foil/Hibachi structure. In addition, about 15% of the beam's energy is lost to microwave radiation. Modeling and simulation suggest that a tuned slotted structure in the cathode should eliminate the instability. We have characterized the electron beam energy deposition in the foils, hibachi, and KrF gas for both the stable and unstable beams using the 3D ACCEPT code from the Integrated Tiger Series of coupled electron/photon transport codes. Results from these calculations will be presented.
- Publication:
-
APS Division of Plasma Physics Meeting Abstracts
- Pub Date:
- October 2000
- Bibcode:
- 2000APS..DPPVO1003S